(1) Field of the Invention
The present invention relates generally to sewing machines and, more particularly, to an apparatus for precisely feeding a collarette to a sewing apparatus for automatically attaching the collarette to a garment body.
(2) Description of the Prior Art
Garments such as shirts or blouses are typically manufactured using manual labor. Garment pieces are cut out of stock material, trimmed to proper dimensions, and then sewn together on a sewing machine by a sewing machine operator. Often in garment manufacturing, a piece of material, known in the art as a "collarette", is folded and sewn around the garment neck to form a continuous collar. The conventional method of sewing a collarette to a garment neck is performed by a sewing machine operator in the following manner.
First, the collarette is cut to a size slightly shorter than the garment neck edge where the collarette is to be sewn. Then, the operator positions the collarette on top of the garment body, places the material under a sewing machine and starts sewing. While sewing, the operator must continually maintain the alignment of the collarette and garment body to obtain an evenly manufactured finished product. Additionally, the operator must pull and stretch the collarette during the sewing operation. Stretching the collarette in such a manner will cause the completed garment and collarette to lie flat and have no wrinkles or gathers around the neck when worn.
The operator may also be required to attach a label (e.g. a manufacturer's identifier having the manufacturer's name and product information) to the garment with the same stitch being used to attach the collarette to the garment. To perform this operation, the operator must carefully position and hold the label in the desired location while sewing. Additionally, the operator may be required to sew a small strip of material, known in the art as a "display", to the inside of the garment neck to flatten and cover the seam joining the collarette and label to the garment body (the "joining seam"). The display is used to cover the area inside the garment where the joining seam would be partially visible after the garment is packaged for sale, i.e., on the inside back portion of the garment neck. To sew a display, the operator must carefully position the display on top of the collarette and garment body and hold the display in position while sewing.
Further complications to the above-described conventional sewing operation are encountered when the joining seam (known as an "overedge seam") is to be hidden from view from the outside of the garment (i.e. the side of the garment away from the body of the wearer). To hide the overedge seam, an operator must layer the collarette, display, and label on top of the garment body, and use an "overedge stitch" to join the pieces together. The resulting overedge seam is then hidden from the outside of the finished garment.
To sew a collarette, label, and display to a garment body with an overedge stitch, an operator must first manually arrange and layer the materials one on top of the other as follows: garment body, collarette, display, and label. The operator then passes the layered materials through the sewing machine, maintaining them in constant alignment while stretching the collarette as described above. If desired, a second sewing operation is then performed to attach the loose edge of the display to garment body with a cover stitch to assure that the display covers the overedge seam and a portion of the label.
The manual process of sewing a collarette, display, and label to a garment body is difficult and tedious. The quality of the finished product is often variable and is largely dependent on the experience and skill of the sewing machine operator. Moreover, the conventional process is time consuming due to the need to precisely arrange and sew the materials together.
A partial solution to the above-identified problems is disclosed in co-pending patent application U.S. Ser. No. 07/711,659. U.S. Ser. No. 07/711,659 discloses a method and apparatus for automatically attaching a collarette, display, and label to a garment body using, inter alia, a collarette feed means, display feed means, label feed means and a controller means. As disclosed therein, the controller means counts the total number of stitches since the start of a sewing operation. When the total stitch count equals certain predetermined stitch counts, the controller means commands the display feed means and label feed means to feed their respective material under a sewing head. Variations in garment body dimensions often occur within a particular garment body size. For example, a garment neck edge can vary in length from garment to garment within a garment size by as much as plus or minus one inch (+/-1") resulting in an overall length variation of four inches (4"). The use of predetermined total stitch count values based on the start of the sewing operation to command display and label feeding can not account for the above described variations that exist within a garment size. As a result, inconsistent placement of display and label can occur.
Additionally, using a motor to drive the label feed means independently from, i.e. unsynchronized with, the motor driving the sewing head can cause the label to be misaligned when placed under the sewing head and cause the label to skew. Further, feeding the collarette and display material on top of the garment body can obstruct the field of view of the sewing head, making it difficult for an operator to assure the sewing operation is being performed properly. Finally, the layering of garment body, collarette, display, and label can complicate the automation of a subsequent operation necessary to sew the loose edge of the display over the overedge seam with a cover stitch. Specifically, automating the second sewing operation when the display and collarette is placed on top of the garment body would require an apparatus to be able to fold the display underneath the garment body and then to sew "blind" through the garment body and collarette. Such an apparatus would be difficult to construct and operate and would prevent the operator from being able to visually check whether the display has been folded and sewn properly in the second sewing operation until after the operation is complete.
Another partial solution to the above-identified problems is disclosed in U.S. Ser. No. 07/711,315. U.S. Ser. No. 07/711,315 discloses a collarette feed means, display feed means, label feed means, a seam detector means, and a controller means. As disclosed, the placement of the collarette, display, and label is determined by detecting the presence of the garment body shoulder seam. As a result, the collarette, display, and label are accurately placed on a garment body. Additionally, feeding of the collarette and display is performed underneath the garment body allowing for a clear view of the sewing head and for simplifying the joining seam.
Both co-pending applications require manual feeding of the garment body through the sewing head. Manual feeding of the garment body would often yield an inconsistent finished product and require constant attending by the machine operator. Thus, there remains a need for an apparatus for automatically feeding one edge of a textile article to a sewing machine.